Adds the ability to close the email detail/thread detail view by pressing
the ESC key, following the same pattern used for closing the composer.
Changes:
- Add closeThreadDetail to MailViewActionShortcutType enum
- Map ESC key to closeThreadDetail in AppShortcutManager
- Handle closeThreadDetail action in HandleMailShortcutActionsExtension
Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>
Martin Kask